C6711 capabilities

Rudi Kroch said:

I'm just starting to get  into using the DSP field and was tasked to program a condition monitoring application for it (in simulink).  I was given the C6711 hardware to peform this on, though. Sadly, at the time I confess I didn't know enough about the field to make a sound judgement and took a colleague's word that the hardware would be capable of performing this task.

With a positive attitude, I am sure you will succeed, impressing both your superior and your colleague.

Rudi Kroch said:

Sensor compatibility - It seems as though the device is designed for audio applications primarily.  Not condition monitoring, I need to use an accelerometer.

The C6711 may have been originally targeted for audio applications, but it will very likely be superb for your application, too. The McBSP is very flexible and can connect to a variety of serial-protocol devices. Otherwise, the EMIF is capable of interfacing to an asynchronous memory-like interface.

What do you need to match to connect your accelerometer? Does it use a parallel or serial interface? Will it connect directly to either of these ports, or will you need to add an adapter of some type.

There are companies like Link Research that make adapter boards for TI DSP EVMs. These can include other connectors or just prototyping area to allow you to add some simple CPLD, if needed, in order to get your accelerometer connected.

But this is all just part of the fun of engineering, figuring out how to connect one thing to another. At least it is the first part of the fun process.

Rudi Kroch said:

Execution time - As far as I could ascertain, the device processes the data in real time, but I require the device to make a measurement, store the data, process the data and give an output. I'm aware of the possibility of using frames, but my version of Simulink does not support frame-based data in the embedded matlab function block.  Only sample based data.

At an 8KHz sample rate, you have 15-30K instruction cycles to do your "process the data" step, depending on the speed of your processor. If this is not enough, then you need to optimize the algorithm or get a faster DSP. If your output is an LED, you do not really need to be generating highly complex results at an 8KHz output rate. And monitoring an accelerometer probably does not require more processing performance than you have available. But with what little I know about it, I cannot say that for sure. But I will give you a 99% chance of success anyway.

Rudi Kroch said:

Memory - Typically, the application requires 15s of data (sampling frequency of 8kHz - maximum of the device, might just be enough). If I read the specsheats correctly, the device has a memory in the kB range.  This will undoubtedly be too little.

If your "C6711 hardware" is the DSK, it comes with 16MB of SDRAM. That will store 2000 seconds of 8KHz samples of bytes. You might want to move the data in/out of internal memory in smaller blocks during processing, but try it with the data all stored in SDRAM first. The cache might make it work just fine for you.

Rudi Kroch said:

At least it does have LED lights, which would be perfect for the output.

Any opinions about my assesment of the siutation would be very helpfull.  I'd like to get my facts straight before taking this matter up with my superior, so that we can decide what to do next. As I said, my knowledge of the field is still not ideal..

My opinion is that you have listed all of the correct categories to be concerned with. Now you must fill in all the detail before you will know what works. We have a huge variety of DSPs and MicroControllers, it is absolutely true that you will be able to do this with something from the TI product line. My gut feeling is that the C6711 will easily do the job, but you will know for sure once you get the details figured out on the hardware interface and the software requirements.

Good luck!